SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fae05040168a7b8eb18d91f11b4a31fe92ce1385d06135a106f20f814ff2c11c' 
  AND token = 'U/HaTqQ7hvtJG8oYCcjXTo7uGpDGfKKnPBMKzgFYvmY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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