SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f077b795601a71f23e23406951c16c980a2bc3eba9db532574421634351b14fa' 
  AND token = 'CDsWVdgcmVHVslQ3xM1Ge/EQDQfgwH/2hhxkmYiz/AY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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