SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be7ae504a7bd375ccd2b858d374f2a76d2f9cf38299f3d3a5fe749ed78083e8b' 
  AND token = 'vyojKNsuBeQnDOPPh9+pCnyKJUGqLkVHPLbx3tFH76o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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