SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b0e745f839b3c31780e3130886aa1e5cea67951c4832ac075de17b4252f0014a' 
  AND token = 'LLVtTQGP6vyalngvyN6y/50RbxHmWOxLATF+uCJPtAQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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