SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd47edbc9e18d2e174fe4fd1f38c70d6bf9a62040a8b26ded5135ee679607b15' 
  AND token = 'r+vUIOcHPVT01JhhkyGSXdc+wWbCvo7bqqCib/6a0jY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}