SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6ef8992c3a1e0827259565446f90aa08c692530ad422bf1dc2fecf6a39eb5d4a' 
  AND token = 'cULUPNI4gTi4z9WmYCKHc59rpFbYm5/IBqY5mLVB44U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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