SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c737d5af28e0974045c6052197d2371adad3056ddb5605c4c336af91f2ce0662' 
  AND token = '+OEPI9vKaAaxQtNFGQ98xXM4ufCyNTRAsKJV3Wa+kv8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}