SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '114d322bde889b4a917a5940a21de637143d0dd3422c721546475c40268ac0f4' 
  AND token = 'MgJlRpTkVN+mXwAAkmPXCX0UXKv/MwgoxCAmfxye7/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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