SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e64e989f769932624e39f77dee793b765ed3e4712ca7434959c135da97cc2325' 
  AND token = '1i/hCGreEoCudrGQugnpirvbBMgeqZoncm6z21F6P34=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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