SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '50564040d3672b6cbd019d15ee3a500373705d6606a766e63f5509044f3bf97f' 
  AND token = '8IzWhUXiQVG6K2qHKKBCwi72EF+duA6fJAZO6SPayfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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