SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d74445fbe688e514aac67b14f943f18c7cb76d6f8e6601ca5b4089be31e6c46' 
  AND token = 'O8lLoJECeEAOjIobLfKY0pBhY8V2JNOP4IWDrcqGHIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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