SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fb8d038bf8269fb0aae77ed081ed3f1bb4732fc6e2a1e625ff177bbf6c0faf62' 
  AND token = 'bdf4EWLkm1VbKBDZiUXNncXMC6YPMJotwD3vvHXX0H0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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