SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b7f06cc48322eb8a6b31a4a0f3cdaa14490069db118727ee0e1db90e1858771' 
  AND token = 'ELqzLU5+pljPvFm61CpsIwuRC90aVCYGucMhZwurQJE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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