SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ff9e87fe5240d5d94c1e6f294868850dc0785247e902adeb7420ac49ba5ce757' 
  AND token = 'DbagtxT20pfLSrJZ2d7GGWeAxa3aL1DzrnFT1wECOoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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