SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ff848754a4ec93aed66eda545c2163ab1ab4e0529ab000f2cca483f3ea890b32' 
  AND token = 'mt/FVb75wGtzRq9zqGFsTXKTFY9rN/tE8rnPE+Jmw1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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