SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b7626c03e05d4cf5f9e79836717c3a3da73f215e217a49d28392039198d97b70' 
  AND token = 'Xx4JNMuoHiY7H1wsEuk8qXM9rNtowjGxKNP1PlnqZ9U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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