SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d45263028b3ad37dea59dc5ebf47e3aad6afec8d2987f50ab8a80457f5bdb7d' 
  AND token = '1na+vow+1O3JHnmm2HqvxFxaxaP6kLbzMJUzqr+YjtA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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