SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d09ec4d580d4f055345a93e8fa7b5a1d99b68d67f8bc41da6c6a6c968750017' 
  AND token = 'KZWYvRh7HT8/01pKboOezMu5r5tKxpWPZ3upALpHnuw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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